An apparatus for supplying a treatment fluid to a well portion is described, in which a container is provided with a fluid chamber which is in closable fluid communication with at least one first outlet. A method of supplying a treatment fluid to a well portion is described as well.
During the production of hydrocarbons, scaling often occurs in pipe bores and passages of different types. Especially when this occurs in downhole installations, it may have serious consequences as the scaling may block the production. Therefore, great efforts are made to prevent or mitigate scaling. If scaling has been established, chemical treatment will often be a preferred alternative to remedy the situation. The drawbacks of chemical treatment, especially acid treatment, are large. Acid treatment may cause great corrosion damage in well installations, for example. This is not least due to the fact that the acid is often pumped down the wellbore as a so-called “pill”, that is to say an amount of acid is brought into a well pipe and is followed by some other well fluid which forces the acid volume forward in the pipe until it has reached its destination. After the prescribed treatment time is up, the acid volume is forced out of the well again. During such treatment, all the well components that get into contact with the acid are subjected to corrosion. Acid may also be forced into the formations around the well, damaging them. The corrosion damage may lead to functional faults in equipment and, at worst, there may be blowouts or other incidents that destroy the well and harm the environment.
To be able to transport smaller volumes of chemicals to a treatment point, a so-called “dump bailer” is often used, that is to say a container that, in a given position, may discharge a volume by a discharging mechanism being activated.
From US2010/0155054, a dump bailer is known, including a chamber holding the material to be discharged, and an outlet for the material. The chamber also includes a movable piston assembly, enclosed in which there is a volume of pressurized fluid, and this may be released via a controllable valve and push a piston against the material so that this is forced out of the outlet.
EP 1223303 discloses an apparatus and a method for injecting a treatment fluid into a subterranean well. A pressure applied to the apparatus through a pipe carrying the apparatus into the well activates a piston which forces the treatment fluid out of the apparatus into the well. The apparatus may include several fluid chambers for selective, incremental ejection of the fluid and treatment of one or more zones within the well.
From US 2010/122814, a cable-operated apparatus for placing drilling mud in a well is known. The apparatus includes a container holding the drilling mud. The container is attached to and may be detached from a packer. At a predefined pressure, a discharge valve activates a cross-over tool which is operatively connected to the valve. Activation of the valve provides for the drilling mud to pass into and through the cross-over tool and be discharged into the well.